Banana plugs should be around 5 dollars per plug in my book - and that will suit your gear nicely. ProAv ones are okay, I used to have them at home. I currently have Audioquest plugs on my Type 4 cable, but I think they're a little light construction wise (I've accidentally bent one already). I personally prefer QED's crimping method, but they're considerably pricier and you need to beg / borrow the well expensive crimping tool.

In regards to cable, don't go overboard, instead investigate the opportunity to biamp the front two speakers...

I have heard about bi- amping one mate said its daft - other mate had it set up and it made a difference as he had removed the link but is it really worth it and what am I achieving? I am no audiophile just what to get the best out of what I have.

Make sure you are familiar with the difference between bi-amping and bi-wiring first. Bi-wiring is of little benefit until distortion levels (it's where you remove the link plates on the back of the speakers and run a cable to all four speaker terminals. Horizontal bi-amping, on the other hand, involves utilising the spare zone 2 terminals on the back of your receiver, and hooking them up to the speakers.

First us, remove the binding plates on the speakers. Then you plug the 'Front Left + Front Right' amplifier terminals into the bottom two speaker terminals. This ensures that the front amps control the bass drivers of your Wharfedales. Then, run cables from the zone two amplifier terminals on your receiver, into the top two speaker terminals. This ensures that the mid-range and tweeters are driven independently from the bass drivers. To finish up, head into the menu of your amp (under manual setup) and choose the 'bi-amp' option.

The downside... You won't be able to run a second zone, but to my ears, the performance is considerably improved when it comes to challenging (musically frantic) tracks.

Oh yeah, some people will also vertically bi-amp their speakers with a separate power amplifier... but seeing as your RXV673 doesn't have pre-outs to allow this, well, it doesn't really matter.

On benefit of passive bi-amping is that there's no longer any electrical interaction between the drivers. Or, to put it another way, if the woofer starts distorting, then it won't effect the other drivers. Also, there can be some distortion reduction since power output is reduced in the amps. It's small, but with lower current draw you may hear a benefit.

It's not a bandaid, it's a choice. If it sounds better it will be a great option. If it doesn't, you've invested next to nothing :-)

If you want speakers with superbly built crossovers that won't benefit from passive bi-amping, you're spending more than a set of brand new Diamond 10.6's would cost. Try it, listen, decide. It's audio after all.